ss = "hello"
print(ss[1])

print("-----------------------判断")
print("abCD".isalpha())
print("123".isdecimal())
"".isnumeric()
"".isdigit()
print("abc".startswith("a"))
print("abc".endswith("c"))

print("-----------------------查找")
print("abcdef".find("b"))
print("abcdef".find("x"))
print("abcdef.com".rfind("."))
print("abcdef.com".replace("c", "C", 1))

print("-----------------------切割")
print("ab|cd|efg".split("|"))
ss = "0123456789"
print(ss[4:7])

print("-----------------------去空白")
print("  abc  ".strip())
